SOLUTION: find the exact value of sin2x, and tan2x given cosx=2/3 and x is in quadrant 1

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Question 1162707: find the exact value of sin2x, and tan2x given cosx=2/3 and x is in quadrant 1
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
find the exact value of sin2x, and tan2x given cosx=2/3 and x is in quadrant 1
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Here's how I would do it:
Step 1, find the sin(x)
sin%28x%29+=+sqrt%281+-+cos%5E2%28x%29%29
Step 2, find the sin(2x)
sin%282x%29+=+2sin%28x%29cos%28x%29
Step 3, find the cos(2x)
cos%282x%29+=+sqrt%281+-+sin%5E2%28x%29%29
Step 4, find the tan(2x)
tan = sin/cos
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If you don't know how to do that, it's time to learn how.